That’s depleted uranium you’re referring to, which is not the same thing as U-238. Depleted uranium contains small amounts of other isotopes other than 238 which are only found in spent reactor fuel, as it says in the link you posted. Even so, we use depleted uranium in tank armor and ...du tank ammunition. Even it’s not very radioactive. It’s effective because of its density, hardness, etc.

Look, the whole point is that it would be a lot less incorrect if the book just said the rounds are coated in “a toxic mix of radionuclides.” No need to put such a fine point upon it.

Even though it is only "weak" radioactive, it is still dangerous if you get it inside you (which of course is the sole purpose of a weapon).

Inhaled or ingested, yes.

Injected is another matter. It’d have to be in solution or perhaps powdered and even then this is a terrible way to go about it. The way it is written, the bullet tears it’s way through flesh and bone and then explodes. In doing so, it has also delivered a fairly toxic and slightly radioactive payload. Totally pointless.

On a similar note there has been some discussion in the Year Zero-discord about the Helium-3 that is used as plot device in Chariots of the Gods. In the text it says that it is highly flammable, but Helium-3 is not flammable.

If you use Deuterium or Tritium (two isotopes of hydrogen) instead it is more scientifically correct since they are highly flammable and rare. Both Deuterium and Tritium is also thought to be important in future fusion reactors so they should be valuable in the Alien world.

The thing about the radioactive ammunition that bothers me is that the rounds would also have to stay in the body to be remotely effective, many soft targets will have an exit wound. Depleted uranium may have desirable properties for armour piercing, but unless you’re fighting Terminators, they’ll provide little advantage over less exotic projectiles.

The purpose of DU rounds is to increase the mass density, and thus penetration, of a given diameter round. DU can be hardened harder than most steels,, but at about 40% more mass per unit volume,.. you want maximum force behind minimum diameter. DU allows doing this. The radiation is not the purpose.

The radiation is just enough to be a health hazard to the user. Or if left in the body, to the the victim, but only YEARS later.

The actual risk level is just high enough the US Veteran's Administration is collecting exposure related data ... to figure out just how much a risk it really is... it's more dangeorus for heavy metal toxicity than for radiation risk.

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